G-Code is the name for the language that is used to tell machines what to do and how to do it.

G-Code is the name for the language that is used to tell machines what to do and how to do it.
A typical piece of G-code would look something like this:
gcodeeeeeeeeee.jpg

What does this code mean? Well here's a quick list explaining letters, and potential strings, that would be written and sent to the printer:
gcode_chart.jpg
For all of the codes, most people would reference http://reprap.org/wiki/G-code because not only does this page give Gcode letters, but explains their purpose and meaning.

In order for the printer to understand the stl files (the 3D model), they need to be compiled into G-codes. This is done with

the help of a Gcode generator. There are a few programs available for download, but the one most commonly

used is called Skeinforge.

Video of how to generate g-code with skeinforge: http://www.youtube.com/watch?v=tjAd1wkSbTM

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